Design your smile!

The desire of every patient who comes to a dental clinic is a beautiful smile. After all, it is the smile that often determines our attractiveness and gives us confidence. But the concept and the performance of prosthetic work in the past did not always coincide. In the past, dentistry was unpredictable. The project was born in the dentist’s head, the dental technician was given an order and the patient took his word for it that “it will be fine”. Tooth shape and size was an estimate, which often involved multiple adjustments. Over time, digitalization has led to the development of smile design, and thus the development of tools that allow for quick correction and individualization of the treatment plan.

Over the past 30 years, dentistry has undergone a major revolution. Currently, the patient’s needs, expectations and satisfaction occupy the most important places in the course of individual stages of treatment. Modern digital dentistry allows us to provide treatment at the highest level.

Thanks to guided modifications using CAD/CAM technology, it is possible to refine the final project, which is the patient’s dream smile. The abbreviation CAD stands for computer-aided design for the visualisation of prosthetic restorations, while the abbreviation CAM stands for computer-aided manufacturing. The production cycle in this technology consists of the following stages: diagnostics, imaging, design, milling or printing, and control of the part embedded in the patient’s mouth.

Modern CAD/CAM systems enable the execution of many prosthetic restorations, including: overlays, crowns, bridges, zirconium oxide restorations, implant abutments, complete dentures, skeletal dentures or occlusal splints. It is also possible to make implant templates, thanks to which complex procedures can be predicted and carried out in a safe way.

Examples of frequently used CAD software are Exocad, 3Shape and Dental Wings. These programs allow you to design temporary crowns and bridges, as well as inlays and onlays. They give the possibility of full manipulation of the design, including rotation, enlargement, mapping of the occlusal surface and changing the depth of the grooves and the height of the nodules. Designing is greatly facilitated by a rich library of ready-made tooth shapes.

A leading method in dental planning and rehabilitation is the integration of CAD/CAM technology with Digital Smile Design (DSD).

The author of the DSD method is Dr. Christian Coachman – a Brazilian technician and dentist. In Poland, the DSD Academy is run by Bartosz Cerkaski, PhD and is called “a springboard to a better tomorrow of dentistry”. Entering the world of DSD is all about patient digitization, virtual treatment, digital presentation, guided dentistry, and digital quality control.

Thanks to communication through visualisation, the patient consciously participates in such a unique experience as designing the smile of their dreams. What’s more, it has the ability to make changes and try on “future teeth” before the final product is made. Patient-dentist communication automatically improves, relationships are built, which increases trust in the doctor. Ultimately, the number of errors is reduced and expectations turn out to be adequate to the result obtained. Digital Smile Design is an inspiration to many. In our practice, we use our own protocol in cooperation with the laboratory.

Digital smile design has a wide range of applications in interdisciplinary dentistry. It allows you to combine aesthetics and function by simulating restoration, all-ceramic CAD/CAM reconstructions or composite direct restorations.

One of the non-invasive ways to improve the aesthetics of your smile is flow injection. This method allows for a very precise and predictable reconstruction of the tooth surface, as well as a change in shape and colour by combining the outer layer of the tooth with the composite. It allows, among others, to repair a tooth chip or close a small diastema. The advantage of this method is predictability, no need for grinding and the possibility of the patient’s participation in the process of designing the shape of the teeth. What’s more, correcting and “refreshing” the effect of the work is possible at any time after it has been completed.

The use of CAD/CAM technology also works well in implantation, as it significantly minimises the risk of complications. Today, you can plan and make an implant guide for navigation. On its basis, the implantologist screws in the implants and, if possible, immediately loads them with temporary crowns prepared from PMMA. This technique allows you to preserve the gingival papilla well and also functions as a great dressing. Thanks to constantly developing methods, It is already planned to skip the stage of temporary prosthetic restorations with accelerated placement of the final bridge.

Orthodontic treatment based on ortho smile simulation enables direct control of the final reconstructive position, while choosing the appropriate strategy of orthodontic movements. Thanks to digitization, it is possible to visually simulate the macroscopic effects of the treatment and the impact on facial aesthetics. By using the appropriate software, we obtain a favourable reconstructive position of the teeth and a minimally invasive procedure. Moreover, 3D technology now enables the production of standard rails and devices as well as their elements such as rings or beams.

Digital smile modelling is also used for overlay treatment with colourless aligner splints. Made of soft, smooth material without metal elements, they are extremely comfortable and allow you to easily maintain hygiene. Without causing pain, they offer optimal treatment and precise results in a short time. Using advanced technologies, we can now visualise the effects we will receive after treatment.

Lava crowns deserve special attention, thanks to which practically everyone can achieve a beautiful smile in a short time. Lava crowns are naturally transparent and can be made in any colour, including the lightest – “Hollywood” white. Made of zirconium oxide, they are biocompatible, very durable and have a high degree of marginal tightness.

The smile project begins with a consultation visit. This is the starting point for creating a treatment plan, so the right amount of time for conversation and clinical examination is crucial. A thorough interview allows you to build a profile of the patient and learn about their problems and expectations. It is crucial to provide the laboratory with relevant information, such as: general information about the patient (gender, age, character traits, treatment budget), proposed shape of the teeth, suggestion of the midline, the presence of dead teeth or teeth intended for extraction. During the clinical examination, the structural risk associated with the loss of hard tooth tissues, the risk of periodontal disease, and the aesthetic and functional risks should also be assessed.

Although we live in the world of GDPR, where everyone wants to protect their information, the consultation should include the preparation of full radiological documentation and digital photography. It is important to have a properly prepared place to take photos, and preferably your own photo studio. Photos of the patient must be taken at an appropriate distance from the lens so that the face is not deformed in the photograph. It is worth noting that the pupils of the eyes are the reference points for any aesthetic analysis of the patient’s face. Hence, the eyes are the most important thing for technicians. There are many digital photo protocols available, including American Cosmetic Dentistry, Dr. Coachman, and Dr. Kois. When creating visualisations, it is important to pay attention to the patient’s characteristics, like their complexion, mouth shape, facial expressions or eye colour. Photos and videos of the patient’s teeth and face are necessary, including technical shots, portraits expressing emotions, frames (including facial, frontal, 12 o’clock, facial profile, occlusal, including casual interview and close-ups).

When taking pictures, it is important to remember about appropriate lighting, positioning the patient from each profile, and faithfully capturing the shapes, proportions, surface details and colour of the teeth. An extremely helpful tool in photography is, among others, the MDP (Mobile Dental Photography) device, which, by emitting light similar to daylight, faithfully reproduces the colour, degree of translucency, opalescence and the effects of the impact of adjacent teeth. Professionally made photographic documentation makes it possible to improve communication with the dental technician without the need for a direct meeting with the patient, which in turn gives the opportunity to objectively assess individual stages of work and shorten the time of order completion.
The next stage of the visit is taking impressions. Today, this can be done by intraoral scanning. Examples of digital registration of the prosthetic field are Carestream scanners. The CS3600 and the wireless CS 3800 are often used. Scans allow, among other things, to map full dental arches and central occlusion, thickness of tooth walls and their texture. The obtained scans allow for the analysis of occlusal relations with opposing teeth and the determination of the size of the contact surfaces.

The latest scanner models enable scanning in real colours and automatic registration of dynamic articulation. In addition, the use of the scanner and its software gives full control over the thickness of tooth preparation for future prosthetic restoration. By scanning, we receive a digital model that is automatically converted into the STL data format, which is sent electronically to the dental technology laboratory.

The smile design is based, among other things, on the analysis of facial features and clinical analysis of the gums. Photos and videos of the patient taken in advance are extremely important here.

White aesthetics takes into account the positioning and proportions of the teeth. During aesthetic planning, we want to design a “positive” smile line, consistent with the curve of the lower lip, as an inverted line can spoil the image. The shape of the maxillary anterior teeth, the characteristics of the lips and the shape of the dental arch convey a strong non-verbal message. The incisors play a significant role here, which is referred to by the “golden proportion rule”. A properly made central incisor with the dimensions of golden proportions looks good in the oral cavity, and this increases the attractiveness of the face, but not necessarily in people who smile with a gummy smile. Fortunately, smile design allows you to visualise the proposed shape of the tooth, including planning perio-surgical correction. In addition, the location of the incisors should be adjusted to the patient’s age – the younger the patient, the more visible the exposure of the upper incisors can be.

What’s more, full lips and southern features allow for the design of larger veneers, while fine features and a thin lip line allow for the creation of smaller, narrower, and slightly longer veneers. The aesthetics of the dental design also refers to the patient’s character traits i.a. four temperaments: melancholic, sanguine, choleric and phlegmatic. After classifying the patient into one of these groups, we can now adjust the appropriate shape of the teeth. The red aesthetic refers to the shape of the gingival garland, which can be modulated, for example, by performing a periodontal microsurgery procedure.
Every project is a new challenge for the technician. The tools of digital dentistry come to his aid. One of the programs used to visualise a smile is Smilecloud. It is mainly used to create an incentive wax-up, which is further used in Exocad. The resulting wax-up digital model can be 3D printed.

Designing a smile frame takes place in several stages, such as determining the horizontal line of the face, the facial-dental midline, the position of the incisal edges, the curve of the smile, the range of the teeth in the lateral direction – buccal corridors, the proportions of teeth, the gingival zeniths curve and the gingival papillae. All this is possible thanks to software that enables full modelling automation. A digital facial arch is used for this purpose, which accurately records the position of the midline of the teeth and face together with the occlusal plane, which prevents the teeth from tilting or shifting. The program applies a grid with a digital ruler to the face, which makes it easier to recognize incorrectly positioned teeth, facial and jaw asymmetry, or tooth midline disorders. The system analyses the best position of the teeth, and also provides guidance on how to make temporary restorations.

Next, the discoloration on the teeth is retouched, imperfections are corrected, restorations are planned (their length, width and position), undesirable gaps between teeth are eliminated, a new smile line, occlusal plane and occlusal height are obtained. Currently, the CAD program designs the work independently, leaving the technicians to control and correct it. For example, in order to fit a crown on an abutment tooth, it is necessary to determine the minimum thickness of the crown, space for cement, the distance from the antagonist and the additional occlusion space. All you need to do is mark the border of the abutment preparation for the crown and the CAD program detects the course of this border and draws it on the abutment.

The presentation of the digital smile design takes place during the patient’s second visit. This is the time to verify their expectations and make possible corrections. Tailoring of the new smile is not possible without the patient’s involvement. The key to patient motivation is to prepare materials with high emotional value. Photos and digital visualisations incorporated into his face and smile provide a strong determination in treatment. The digital platform enables control and elimination of ineffective procedures.

The doctor discusses the simulation and presents a treatment plan. Therapeutic options, costs, and the risk of not proceeding with the treatment are discussed. Once the simulation is approved, the patient undergoes the next steps of treatment while technicians 3D print a model of the smile.

Based on the 3D design received, we make a silicone index, which is used to make a temporary overlay (called a mock-up). The patient’s acceptance gives the doctor the green light for preparation – suitable for veneers, layered or full-contour crowns. It should be emphasised that the digital smile design, and then the mock-up, allows you to predict the final thickness of the crowns and thus ensure minimal preparation of tooth tissues. Today’s dentistry allows for full control over the preparation. Looking at the current progress in dentistry, cutting templates that allow you to prepare and apply veneers in one visit should soon be available.

After teeth grinding, we make an impression or intraoral scan and send it to our technicians who analyse the legibility of the scan and record the occlusion. It is important to note how many errors can be contained in one scan. In the case of distant abutments, the scanner may lose its reference point and the recorded distance between them will be different than it actually is.

Technicians then transfer the scan of the ground teeth to the Exocad design. By applying the previous design, they analyse whether we have enough space for the crowns. Then, the design of the full arch is refined based on ready-made libraries from the Exocad program. The next step is to print the finished design from PMMA (polymethyl methacrylate) resin.

The next visit to the dentist is related to the PMMA fitting. This is the time when the patient becomes familiar with the prototype and can raise any objections to the shape, length and width of the crowns. The patient must be comfortable with the new smile design. We pay attention to the shape, position of the teeth and aesthetic workmanship.

We make a note of any comments and objections, and pass them on to the laboratory. In the case of Lava crowns, the option with the correction requires a virtual cut-back. The option without corrections is cut from zirconia blocks in the full contour. It is cut in a milling machine and then sintered in a furnace. The work then goes back to the ceramist. An experienced technician, based on previous projects, covers the final project with ceramics. Scans are used here as work control. A ceramist scans his finished work on the model and compares it with each other. This is manual work, hence the target product may be slightly different from the prototype. The ceramist uses his sense of aesthetics and proportions, that’s why Lava crowns are so special.

On the last visit, the final setting of the crowns takes place. We can make small adjustments here, such as adjust them in the bite.

The case report presented below contains only a fragment of the patient’s comprehensive treatment. Further stages of treatment, including implant-prosthetic treatment in the lower arch, are not included here. Our goal is to illustrate the importance of digital smile design using the example of the design in the upper arch.

The patient, 38 years old, came to the dental clinic for comprehensive dental treatment.

Previously, she had no way to visualise the final result, let alone try on the project.

In the upper arch she had 12, 11, 21, 22, 23, 26 single crowns, 17 temporary crowns, 16, 15, 14 implants, 24-25 bridge (Fig. 1, 2).

The patient was not happy with the current situation, despite the earlier dental treatments. The lips on the right side drooped, the teeth seemed too short. The bite was changed – it caused abrasions and lesions of the mucous membranes, and wounds on the lips and cheeks. The teeth overlapped badly and the lower bridges were too high.

A thorough interview was conducted. No systemic disorders were found. Disturbed occlusal height caused by missing teeth in the lower arch was noted. Therefore, an analysis of the occlusal height was carried out before re-treatment of prosthetics.

A pantomography and tomographic X-rays were taken in accordance with the protocol of the digital smile design, together with a series of photographs and videos. An intraoral scan was also performed and sent to the DentalArt laboratory.

On the basis of the medical history and intraoral examination, an interdisciplinary treatment plan (implant-prosthetic treatment) was proposed, which the patient fully accepted.

Treatment plan: in the upper arch, root canal treatment of teeth 13 and 24 was proposed, as well as a grind for Lava crowns and their placement on 11,12,13,(14,15,16 – prosthetic crowns screwed on implants),17,21,22,23,24,25,26,27. Chosen colour: BL2.

Based on the patient’s preferences and data sent to the laboratory, reference lines within the face (i.a. midline, horizontal line, lower lip line) and the course of the gingival garland were determined. Facial analysis (pupil line, lip and smile), oral-labial analysis (i.a. smile width, buccal corridor and smile dynamics), dental analysis (general composition, shapes, dimensions, proportions and nipple peaks) and dental-labial relations were performed. The photos were used for visualisation in Smilecloud program (Fig. 3-8) and for the digital smile project in Exocad (Fig. 9-14).

The technicians made, among others, correction of the teeth in length to obtain the correct, symmetrical occlusal plane. As a result, a digital design was obtained. After the design was accepted by the patient, the 3D model was printed (Fig. 15).

First, a hygienization procedure was performed and oral hygiene instructions were given to the patient. Endodontic treatment was then carried out, with root canal preparation and the final filling. Due to abutments being too short and having different lengths, the previous inserts were replaced. Glass fibre inserts were introduced in 13, 12,11, 21 and 22. The abutments were aligned with the planes under the crowns (Fig. 16).

The crowns were removed by grinding them in accordance with the principles of tooth preparation for Lava crowns: 11,12,13,21,22,23,24,25,26. After grinding, another intraoral scan was performed. Using the 3D design, a mock-up of the silicone index was made. Temporary crowns from the A1 Luxatemp silicone index were placed on Rely X (Fig.17). This was followed by an interview with the patient about temporary crowns. After approval, the final crowns were placed (Fig.18).

The patient is an example of the importance of digital smile design – one that is accepted by herself, does not raise any objections, and at the same time is aesthetic and functional. The patient had the opportunity to “test” her future teeth and make corrections at every stage of the project. This is an incredible comfort and inspires confidence in the doctor. As for doctors, on the other hand, we have the opportunity to communicate well with technicians and complete the project quicker.

Digital smile design allows for a more dynamic synchronisation of work between the dentist and the technician. It allows you to simulate all solutions before touching the patient’s mouth, obtaining natural shapes and to integrate more effectively with the face. The possibilities created by digital dentistry have a strong impact on the patient’s emotional motivation – they are more determined to undertake appropriate treatment and follow the dentist’s recommendations.

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